Question
Help please.
A poll found that people from the north now have relatively warm feelings toward people from south. A poll. Conducted by among a random sample of 110 adults, found that 476 of sampled consider that two regions friends The margin of error to the poll was plus or minus 35 percentage parts for a 0.95 confidence level). Use this information obtain a 95% confidence interval for the Percentage of all northerners who consider the two regions friends. The 95% confidence interval is from % % (Type an integer or a decimal rounded one decimal place as needed)
Explanation / Answer
sample size is not clear so i consider 710
n = 710 , p = 476 / 710 = 0.67 , ME = 3.5% = 0.035
z value at 95% CI = 1.96
CI = p +/- ME
= 0.67 +/- 0.035
= (0.635 , 0.705)